Coordinated Dispatch Of Multi-Area Interconnected Electric-Thermal Combined System

At present,Chinese wind power project is developing rapidly especially in “San Bei” region.Because of the heating period in the “San Bei” region,there are a large number of heating units.Most of them operate in the mode of “power determined by heat ” and the wind power output is random and intermittent,which lead to the insufficient of the units' downward standby capacity and a large number of wind power curtailment,also obstruct the development of wind power industry.Therefore,increasing the units' standby capacity and improving the system's flexibility to reduce the curtailment of wind power is becoming the research emphasis in recent years.After analyzed the key factors causing a large number of wind curtailment in the combined heat and power system,this paper mainly studies the ways to improve the local accommodation of wind power and optimize the dispatch.Firstly,aiming at the local accommodation of wind power,this paper considers adding thermal storage devices,electric boilers and electric heat pumps to the traditional combined heat and power system.A heat and electricity coordinated dispatch model is constructed to study the effects of the three devices on the wind power accommodation ability of the combined heat and power system.Also,the effects of various combined operation schemes of the three devices are analyzed through specific examples.Then,considering that the wind power can be fully accommodated by the interconnection of the power subsystems in combined heat and power system,a multi-area parted dispatch model is established to study the influence of the parted dispatch model on the wind power accommodation under the constraint of the tie-line.And the feasibility of enhancing the wind power accommodation ability by this multi-area coordinated dispatch is verified due specific examples.This paper also analyzes the influence of system parameters such as wind power installed capacity,electric load and heat load on the wind power accommodation.Finally,this paper proposes a multi-area electric-thermal coordinated dispatch mechanism under the relaxation of tie-line constraint to solve the restriction on wind power accommodation caused by tie-line control.Based on the above research,a multi-area electricthermal coordinated dispatch model is established,and the impact of the mechanism on improving system's flexibility and wind power accommodation ability is analyzed through specific examples.